Bushes, also known as bushings, are components used in automotive suspension systems to provide cushioning and flexibility between various parts. Replacing worn bushes is a common maintenance task in automotive repair, to restore the vehicle's suspension performance and ride comfort. The primary functions of car bushes include:

​

1. Vibration Dampening: Bushes absorb and dampen vibrations generated by road irregularities, bumps, and imperfections, thereby improving ride comfort.

2. Isolation of Noise: They help isolate and reduce noise from the suspension system, preventing it from transmitting into the cabin of the vehicle.

3. Flexibility: Bushes allow for controlled movement of suspension components while maintaining stability and control of the vehicle.

4. Cushioning: They provide a cushioning effect between metal parts, reducing wear and tear and extending the lifespan of suspension components.

​

Over time, bushes can wear out due to constant exposure to mechanical forces, temperature, chemicals and dirt ingress. When they wear out, they can lead to symptoms such as clunking noises, excessive vibrations, and poor handling. Therefore, regular inspection and maintenance of bushes are essential for ensuring the proper functioning and safety of a vehicle's suspension system.

​

Polymer based bushes

Economy suspension systems generally utilise rubber bushes, they are cost effective, easy to manufacture, and replace. They offer comfort, vibration damping, flexibility, and satisfy the basic requirements of the suspension system. However, they are not precision bushes. They distort under load, which is necessary, but this also means that their points of pivot and rotation move. This results in minor changes in suspension geometry, although mostly un-noticeable in their intended application. The suspension movement requires joints to rotate to allow the system to work as intended, but with solid rubber bushes this means that they move by distorting the polymer part of the bush, they do not rotate freely, they twist and distort. This not only results in a movement of the rotation pivot point, but requires an ever increasing force input to move and rotate the bush to the extremes of the system positions. This distortion results in a limited service life of the bush. It also requires that the fitment of them requires particular attention to be given to the linkages to these bushes being tightened in a loaded condition, if this is not done properly, the rubber bushes tear and fail early. It is worth noting that if the polymer part of the bush deteriorates, this can result in a relatively large movement within the bush with serious safety implications. 

​

Precision spherical bearing bushes

Performance Bushes, design, manufacture, and sell, precision spherical bearing bushes. These type of bushes are vastly different from standard rubber and polymer bushes. They are a precision engineered, single point of rotation mechanical joint, with 6 degrees of freedom, allowing full angular and rotational movement about and across the pivot point. They are used where the automotive manufacturer wishes to have known pivot points in advanced suspension systems.

Not to be confused with a standard "ball joint", a correctly designed spherical bearing bush, will not only provide a known precision pivot point, but will provide that pivot point with a very low friction force input requirement. A conventional "ball joint" does not do this, as it is based on a highly stressed polymer component, which results in a very "stiff" joint requiring significant force to move. Any additional force required, to move the pivoting mechanism itself, is misdirected energy and "drag" within an advanced suspension system. This is acceptable in standard suspension arrangements, but where the car manufacturer has installed an advanced suspension system, with the related components intended to do exactly and only what they should be doing, then only a low friction properly specified spherical bearing joint is appropriate.